#!/usr/bin/python
# -*- coding:utf-8 -*-
# @author  : micah
# @time    :  
# @function: 
# @version :


class Animal:
    def bark(self):
        print('动物在叫')


class Person(Animal):
    def bark(self):
        print('人在说话')


class Dog(Animal):
    def bark(self):
        print('狗在叫')


animal = Animal()
person = Person()
dog = Dog()

animal.bark()
person.bark()
dog.bark()

